Synchronizers are used to synchronize the speeds of a sleeve and a clutch gear before their corresponding teeth engage, to avoid double clutching. Conventional synchronizers include a sleeve, a synchronizer ring, and a clutch gear. When a driver shifts into a gear, the synchronizer sleeve is moved toward the gear. As it moves, the small teeth on the sleeve engage the teeth on the synchronizer ring, causing the synchronizer ring to rotate at the same rate as the synchronizer assembly, which are splined to each other as well as the output shaft. As sleeve continues to move toward the gear, the inside of the synchronizer ring is pressed up against the conical shaped part of the gear. This causes the gear to match speed with the synchronizer, and once the speeds are matched, the synchronizer sleeve continues to slide toward the clutch gear, engaging the teeth on the side of the gear.
However, spline alignment of a sleeve and a clutch gear of conventional synchronizers cannot be ensured. Further, the speed difference between the sleeve and the clutch gear due to a break down of presynchronization causes the sleeve and the clutch gear to collide with one another. Accordingly, such a collision causes noise and motion during shifting. This noise and motion are both heard and felt by the driver, which is highly undesirable. Accordingly, a synchronizer that reduces such noise and motion would be highly desireable.